WATER MANAGEMENT FOR MARINE AQUARIUMS 



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Figure 2. — Typical closed sea-water circulatory system. The water flows as follows : Holding tank 

 (black) to return trough and pipeline, to manifold aerator, to filter, to manifold aerator, to 

 reservoir, to pump, to supply riser, to gravity tank, to supply pipeline, to holding tank. Note 

 that all service units, except the gravity tank, are in duplicate and that valves are arranged 

 to provide complete flexibility — that is, all possible combinations of units. The holding tanks 

 are connected to two supply pipelines, and a length of flexible hose from each overflow makes 

 it possible to use either return trough. 



""closed.'' A typical '"open" sea-water sys- 

 tem has been described by Hinton (1958). 

 In this, the water is used once and then dis- 

 carded. The tanks of such a system should 

 be connected in parallel to the water 

 source, not in series, so that each tank re- 

 ceives the same kind of water, and disease 

 cannot be spread through the water from 

 tank to tank. Both Hinton (1958) and 

 MacGinitie (1947) point out that the stor- 



712-029 O— 64 2 



age tank, which provides an emergency 

 supply of water if the pumps fail and also 

 acts as a settling tank, should not contain 

 more than a 86-hour supply and that a 24- 

 hour supply is usually sufficient. 



In order to prevent the spread of disease 

 and facilitate water treatment, each tank 

 should have its own circulatory system 

 with an individual pump, filter, and res- 

 ervoir, but the expense of initial installa- 



